Torsional pivot-balance



(No Model.)

I. A. ROE-DER.

TORSIONAL PIVOT BALANCE. No. 340,006. 4 I Patented Apr. 13, 1886.

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. UNITED STATES PATENT OFFICE.

FREDERICK A. BORDER, OF CINCINNATI, OHIO, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO THE UNITED STATES TORSION BALANCE AND SCALE COMPANY, OF JERSEY CITY, NEIV JERSE TORSIONAL PIVOT-BALANCE.

E'EEGIPICATION forming par: of Letters Patent No. 340,006, dated April 13, 1886.

(No model.)

To aZZ whom it 72107 6072.067'521.

Be it known that I, FREDERICK A. ROEDER, a citizen of the United States, residing at Cincinnati, Ohio, have invented new and useful Improvements in Torsional Pivot-Balances, of which the following is a specification.

My invention relates to torsional pivot balances or scales in which the pivotal bean ings of the beam and scale-pans consist of metal supports acting torsion-ally between holding-ahatments, and'is in the nature of an improvement upon Letters Patent No. 262,907, granted to me August 15, 1882. In said Letters Patent I described the use of stretched metallic wires acting torsionally, which, as illustrated in the drawings therein, were wires of circular section. In the use of wires of cir' cnlar section a practical diiiiculty exists, increased in larger balances employed in weighingheavy bodiesin respect to the mode ofsecur ing the wires in their fastcnings, the circular form being diiiicuit to properly secure against the twisting action of constant use. This difficulty is ofcourse magnified in largerscales, where the wire is enlarged into a metallic rod and used at relatively shorter reach, owing to the increased leverage of torsional action against the holding power of the fastenings, and as the metal employed is usually steel or some metal admitting a high temperg; to secure elasticity, it is not desirable to square the ends or places where the holding devices are attached, and still less so to flatten and pierce them for rivets, as such changes involve a loss of elasticity and strengtlnseriously impairing the proper action of the balance by reason of the necessity of heating such ends as a condition of the squaring operation. Moreover, even the heat can ployed in soldering or brazing affects the temper injuriously, and it is often impossible to obtain a perfectly-secure fastening in holding the circular wire against torsional strains by solder applied to its cylindrical surface. I have found a remedy for these diilieult-ies in the employmentof wires or rods of angular or elongated cross-section, which, while possessing all the torsional advantages of cylindrical wires, admit being secured in holdiugsockets of corresponding form.

In carrying out my present invention I do no not confine myself to any particular form ofcross-section for such torsional pivots, since a pivot having a cross-section of any geometric figure (other than circular) will serve the purpose in view.

In the drawings herewith illustrating my invention, I have shown in Figure 1 a perspective view of the supporting-irame of the central pivots of a double-heani scale. Fig. 2 is a cross'scctional view of the pivotal wire in its contaihing-socket. Fig. 3 is aperspective view of one of the terminal frames. Fig. 4 is a cross-section of a triangular pivotal wire in its socket, and Fig. 5 exhibitsafew cross-sections of other forms of pivotal wires which may be employed in carrying out my invention.

For the purposes of present description I have shown in the drawings a supporting frame for the central pivots of a double-beam scale, consisting of two side standards, A A, and intermediate cross-braces, B B. Between the standards in parallel horizontal lines, are stretched the pivotal wires a a, that sustain the scale'heams b b. The upper ends ofthe standards A are recessed by an open slot, a, corresponding with the cross-section of the pivotal wire employed. Thus, if a wire of square section is employed, as in Fig. 1, the recess is rectangular of a corresponding width; or, if a wire of angular section is employed, the recess is formed to a corresponding angle, as in Fig. 4. The apertures at c, for the passage of the lower wire through the standards A, are similarly formed to accommodate the wire employed. In practice but a single wire is used, the ends being brought together and secured at the side of one of the standards, as at s, Fig. 1.

In the case of the terminal frames F, Fig. 3, open slots at the upper and lower ends of the vertical posts fserve to engage the wire, the'cnds of which aresecnred at the side of one of the posts, as before, and the wires are secured in correspondinglyshaped notches in It will be readily perceived that the sides of the recesses or apertures form abutments,

which hold the pivotal wires against torsional strains, and that no other fastening is required. The wire may therefore be at once placed in position and stretched without any manipulation affecting its temper or elasticity, and that I it will be securely and far more durably retained in such position than by soldering. It will also be obviousthat these advantages may be attained by a wire having one orany number of plane faces in its peripheral surface.

I claim as my invention and desire to secure by Letters Patent- 1. In a torsional pivot-balance. in combination with the beam, a pivot of other than cir cular cross-sectiou,tensioned between holdingabutmeuts and secured to the beam in correspondingly-formed sockets, whereby the pivot is held by its engagementin said sockets without other fastening against rotation, as set forth.

2. The combination, in a weighing-balance, of pivot-holding abutments having sockets, as described, duplicate scale-beams suitably connected, and a single wire of other than circular cross-section stretched and returned between the hi lding-abutmcnts in parallel lines, constituting fulcrmn-pivots for the duplicate beams, and engaging the beams and holdingabutments in correspondingly formed sockets, forming a rigid connection against rotation therein, substantially as set forth.

3. In a torsional pi ot-balance, in combination with the balance-beam, a terminal pendent frame having plane-faced sockets at top and bottom, and a torsional pivot of other than circular cross-section stretched upon the frame and engaging in said sockets by means of its.

said plane faceor faces, substantially as set forth. v

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

FREDERICK A. ROEDER. 

